1. Field of the Invention
This invention relates to efficient storage of pressurized gases and liquids having high natural trans-migration rate which makes them difficult to store over time without a calculable loss rate through the storage enclosure. Hydrogen gas storage therefore is difficult thus limiting its commercial use as a portable energy source.
2. Description of Prior Art
Prior art storage of hydrogen gas or in a liquid form has required relatively large volume storage tanks which by their very nature, composition and size are very heavy and therefore preclude their expanded use into useful energy using venues such as automobiles and other modes of transportation and stationary energy sources. The low temperature of liquid hydrogen requires substantial insulation and specialized transfer equipment all of sufficient strength and thickness to withstand the internal pressure and cold associated therewith. Such attempts to solve these storage problems can be seen, for example, in U.S. Pat. No. 6,347,719 directed to a lightweight liquid hydrogen storage tank utilizing dual wall storage vessel which is segmented into multiple radial chambers. Each of the chambers is evacuated to a high vacuum which along with the composition of the outer shell a complicated sandwich having a low conductive nature is required.
U.S. Pat. No. 4,461,398 is directed to a storage tank for liquefied hydrogen gas which defines a multi-wall enclosure with thermal insulation between the walls.
U.S. Pat. No. 4,154,364 discloses thermally insulating containers for liquid gases having a double wall storage container. The gap between the walls is evacuated to a high vacuum and a gas absorbing material is provided in the vacuum.
U.S. Pat. No. 6,371,323 claims a double walled poly-steel storage tank having an outer steel wall tank and an inner tank of thermoplastic material with the tanks bonded together by multiple accessory fittings. The space between the tanks have leak detection equipment associated therewith for monitoring the internal tank leakage should it occur.
In U.S. Pat. No. 3,924,773, a fuel tank is shown in which a double fuel tank is claimed having an inlet and a pressure relief valve in communication with the area between the tanks which acts as a safety layer which upon rupture dispenses carbon dioxide gas to suffocate fuel fires should the inner tank rupture.
A cryogenic storage tank is shown in U.S. Pat. No. 3,919,855 having a dual skinned enclosure wall whose cavity therebetween is packed with insulating material.
All of the above cited prior art is directed to either liquid hydrogen storage or fossil fuel tank configurations which do not address the rigorous storage and transportation requirements of hydrogen gas under high pressure. In such configurations the high vacuum between the walls would simply increase the trans-migration of hydrogen gas. Only applicant's storage system utilizes the inherent trans-migration of hydrogen through the contact wall to affect a seal thereagainst by the inert gas under positive pressure.